My friends and I have made an Uno game so that we can play Uno together when we are across the country. Would I be allowed to upload that game onto itch.io or would I get in trouble with the company that owns Uno?
Those are separate questions. You can upload your game to itch.io; nobody's going to stop you. But the rights holders may very well send a takedown request, and your game could be taken down as a result.
